A variety of control systems are provided on a vehicle for control of drive configurations or characteristics of the vehicle. One such control system is a hill start assist (HSA) system. As is well know, the HSA system automatically maintains a vehicle brake when the vehicle is located on a hill as the vehicle is traveling below some predetermined minimum speed value. Typical HSA systems will maintain the vehicle stationary while the vehicle is on a grade to permit the vehicle operator to start the vehicle in a desired direction of travel while preventing the vehicle from rolling in the opposite direction. Many HSA systems include a variety of inputs for actuating and deactivating the system (e.g., lateral and longitudinal acceleration sensors for detecting vehicle speed and vehicle position angle). Another type of vehicle control system is a brake traction control system (BTCS). This control system controls driving force distribution between wheels according to driving conditions of the vehicle.
Control of drive configurations or characteristics of off-road type vehicle (e.g., all-terrain vehicle, multi-utility vehicle, side-by-side vehicle and other types of like utility vehicles) can be unique to such vehicles. Such vehicles are often capable of being driven over uneven or hilly terrains, and therefore the known HSA systems that are automatically operable based on sensed vehicle position angle can limit HSA usability in off-road conditions. Such vehicles are also often capable of encountering soft, loose or slippery soils as well as snow and/or ice and optimum drive characteristics can vary from rear wheel drive (where only the rear wheels provide traction), front and rear wheel drive (sometime referred to as four wheel drive where the rear wheels and at least one of the front wheels provide traction), and all wheel drive (where the rear wheels and both front wheels provide traction). In some known off-road type vehicles, the operator can manually select the drive configuration (e.g., from rear wheel drive to four wheel drive) which in turn can impact driving force distribution between the front wheels and the rear wheels when terrain surface friction is different between the front and rear wheels.